High severity · published Jul 8, 2026
CVE-2026-56297
FreeRDP - Use-After-Free via Race Condition in DRDYNVC Channel Callback
8.1
CVSS
0.5%
EPSS
No
On KEV
Description
FreeRDP before 3.22.0 contains a use-after-free vulnerability in dvcman_channel_close and dvcman_call_on_receive due to improper synchronization of channel_callback access. A malicious RDP server can trigger a race condition by sending DYNVC_DATA and DYNVC_CLOSE messages concurrently, causing heap-use-after-free in the drdynvc client thread and potentially enabling remote code execution or denial of service.
CVSS vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
High
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.5% · higher than 40% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
FR
FreeRDP · FreeRDP
before 3.22.0 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-56297
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-56297
Exploit
https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-3mv2-5q57-2v8h
Third Party Advisory
https://www.vulncheck.com/advisories/freerdp-use-after-free-via-race-condition-in-drdynvc-channel-callback
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